<!DOCTYPE html SYSTEM "http://www.thymeleaf.org/dtd/xhtml1-strict-thymeleaf-spring4-4.dtd">
<html lang="en"  xmlns:th="http://www.thymeleaf.org">
<head>
    <meta charset="UTF-8"/>
    <title>Title</title>
</head>
<body>
  <h1 th:text="${showtest}"></h1>
  <h1 th:utext="${showtest}"></h1>

    <span th:if="${32>20}">
        成立
    </span>
   <span th:unless="${19>20}">
       不成立
   </span>

  <img src="image/1.png">
  <img th:src="@{image/2.png}"/>
  <a href="hello">链接</a>
</body>
</html>